package com.imooc.mall.exption;

import com.imooc.mall.common.ApiRestResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.validation.BindingResult;
import org.springframework.validation.ObjectError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.ArrayList;
import java.util.List;

/**
 * 处理统一异常的Handler-将响应内容统一转换为ApiRestRespons格式
 */
@ControllerAdvice // 用于创建一个控制器异常处理类
public class GlobalExceptionHandler {
    private final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    /**
     * 系统异常
     * @param e 传入的业务异常对象
     * @return 返回处理后的结果
     */
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public Object handleException(Exception e){
        log.error("Default Exception", e);
        return ApiRestResponse.error(ImoocMallExceptionEnum.SYSTEM_ERROR);
    }

    /**
     * 业务异常
     * @param e 传入的业务异常对象
     * @return 返回处理后的结果
     */
    @ExceptionHandler(ImoocMallException.class)
    @ResponseBody
    public Object handleImoocMallException(ImoocMallException e){
        log.error("ImoocMallException", e);
        return ApiRestResponse.error(e.getCode(), e.getMessage());
    }

    @ExceptionHandler(MethodArgumentNotValidException.class)
    @ResponseBody
    public ApiRestResponse handleMethodArgumentNotValidException(MethodArgumentNotValidException e) {
        log.error("MethodArgumentNotValidException:" + e);
        return handleBindingResult(e.getBindingResult());
    }

    private ApiRestResponse handleBindingResult(BindingResult result) {
        // 把异常处理对外暴露的提示
        List<String> list = new ArrayList<>();
        if (result.hasErrors()) {
            List<ObjectError> allErrors = result.getAllErrors();
            for (int i = 0; i < allErrors.size(); i++) {
                ObjectError objectError =  allErrors.get(i);
                String message = objectError.getDefaultMessage();
                list.add(message);
            }
        }
        if (list.size() == 0) {
            return ApiRestResponse.error(ImoocMallExceptionEnum.REQUEST_PARAM_ERROR);
        }
        return ApiRestResponse.error(ImoocMallExceptionEnum.REQUEST_PARAM_ERROR.getCode(), list.toString());
    }
}
